Trends within the field of packaging machines point toward increasingly high capacity machines intended for rapid, continuous filling and sealing of a very large number of identical or similar packaging containers, e.g., such as containers of the type intended for liquid contents such as milk, juice, and the like. As these machines have increased in speed and decreased in size, the surrounding apparatus of these smaller more efficient packaging machines have had to be modified to accommodate these higher speeds.
Packaging machines are now known that integrate the various components necessary to fill and seal a container into a single machine unit. This packaging process, generally stated, includes feeding blank cartons (blanks) into the machine, sealing the bottom of the cartons, filling the cartons with the desired contents, sealing the tops of the cartons, and then off loading the filled containers for shipping.
Packaging machines may employ endless rotating conveyors that allow various packaging processes to be performed repeatedly as the conveyor transports the cartons between a plurality of processing stations. These endless rotating conveyors include a plurality of carriers that are located around a conveyor loop. The carriers accept individual carton blanks that are continuously fed onto the machine by means of an infeeder, and convey them along a processing path to subsequent sealing and filling processing stations.
Increased throughput and decreased size requirements for packaging machines have increased the demands that are placed on the endless belt conveyors that are employed. The increased speed and decreased size of these conveyors increases the forces on the individual components of the conveyor assembly. The stresses on these components tend to cause increased component wear which, in turn, leads to frequent maintenance and a corresponding decrease in the reliability of the machine. This is particularly true along the arcuate portions of the track where the moment forces are larger than on the linear portion.